Water is a scarce natural resource in many areas such as sub-Saharan Africa where many communities lack reliable water supplies. In areas where water is scarce, usage of traditional flush toilets, which may use from four to twelve liters of water for a single flush, is undesirable.
Toilets that flush using a relatively small volume of water are therefore highly advantageous in water scarce areas. Added to this is the fact that some sewerage treatment facilities such as septic tanks and other biodigestors can suffer reduced performance of the biological processes with increased flows of water.
Several models of low volume flush toilets are known in the prior art. One design of flushable toilet uses a 45 degree outlet and smaller diameter pipe and has a single stage flush mechanism that is similar to conventional designs with water being discharged from the rim of the toilet bowl. The design which is made from injection moulded plastic material flushes using approximately two liters of water.
Another design uses two jets of water to create a double vortex to clear the toilet bowl and also has a subsurface inlet to clear the water trap. The design requires a pump and works on about five liters of water per flush.
For the purposes of this specification the term the water trap is intended to mean the lower at generally U-shaped bend at the bottom of a toilet bowl and wherein the depth of water in the bend is determined by the vertical height of the outlet from the generally U-shaped bend. The water trap therefore has a normal water level in the horizontal plane of a bottom of the outlet from the generally U-shaped bend.
The preceding discussion of the background to the invention is intended only to facilitate an understanding of the present invention. It should be appreciated that the discussion is not an acknowledgment or admission that any of the material referred to was part of the common general knowledge in the art as at the priority date of the application.
There is a need for a flushing toilet that has a low water usage accompanied by acceptable efficiency.